dragon-fly vs mosquito hawk

dragon-fly

mosquito hawk

noun
  • Any of various species of dragonfly of the genus Micromidia, endemic to eastern Australia. 

  • A crane fly (US) / daddy longlegs (UK), a large, mosquito-like insect in the suborder Tipulomorpha 

  • A dragonfly. 

How often have the words dragon-fly and mosquito hawk occurred in a corpus of books? (source: Google Ngram Viewer )